N-phenyltetrahydrophthalimide compounds

ABSTRACT

N-phenyltetrahydrophthalimides of the formula I ##STR1## where R 1  is hydrogen or halogen, R 2  is halogen and A is a substituent of the formula ##STR2## where X is oxygen or sulfur, n is zero or one, R 3  is hydrogen or C 1  -C 6  -alkoxycarbonyl or C 1  -14 C 3  -alkyl which is unsubstituted or substituted by halogen, cyano, hydroxyl, mercapto, C 1  -C 6  -alkoxycarbonyl, C 1  -C 4  -alkoxy, C 1  -C 4  -alkylthio, C 3  -C 6  -alkenyloxy, C 3  -C 6  -alkenylthio, C 3  -C 6  -alkynyloxy, C 3  -C 6  -alkynylthio or C 1  -C 4  -acyloxy, or is hydroxyl or carboxyl or is C 1  -C 4  -alkylthio-C 1  - or C 2  -alkyl or C 1  -C 4  -alkoxy-C 1  - or -C 2  -alkyl which is substituted in the alkyl ether or thioehter moiety by C 1  -C 6  -alkoxycarbonyl, R 4  is hydrogen or C 1  -C 3  -alkyl, Z is methyleneoxymethylene, methylenethiomethylene or ethenylene (--CH═CH--) and R 5  and R 6  are each hydrogen or C 1  -C 3  -alkyl, which are useful as herbicides, are prepared.

This application is a continuation of application Ser. No. 07/279,518, filed on Dec. 5, 1988, now abandoned.

N-aryl-substituted tetrahydrophthalimides having a herbicidal action are known. For example, European Patent 207,894 describes tetrahydrophthalimides of the formula I' ##STR3## where the radicals have, for example, the following meanings: R^(a) and R^(b) are identical or different and each denotes hydrogen or a halogen atom;

R^(c) and R^(d) together denote a substituted or unsubstituted C₂ -C₃ -alkylene bridge, and

R^(e) denotes, inter alia, hydrogen, cyano or C₁ -C₄ -alkyl.

However, the action of these compounds at low application rates is unsatisfactory.

The object of the invention was therefore, to provide N-phenyltetrahydrophthalimide compounds which have, at low application rates, a better herbicidal action on unwanted plants without damaging crop plants.

This object is achieved by tetrahydrophthalimides of the formula I ##STR4## where R¹ is hydrogen or halogen, R² is halogen and A is a substituent of the formula ##STR5## where X is oxygen or sulfur, n is zero or one, R³ is hydrogen or C₁ -C₆ -alkoxycarbonyl or C₁ -C₃ -alkyl which is unsubstituted or substituted by halogen, cyano, hydroxyl, mercapto, C₁ -C₆ -alkoxycarbonyl, C₁ -C₄ -alkoxy, C₁ -C₄ -alkylthio, C₃ -C₆ -alkenyloxy, C₃ -C₆ -alkenylthio, C₃ -C₆ -alkynyloxy, C₃ -C₆ -alkynylthio or C₁ -C₄ -acyloxy, or is hydroxyl or carboxyl or is C₁ -C₄ -alkylthio-C₁ - or -C₂ -alkyl or C₁ -C₄ -alkoxy-C₁ - or -C₂ -alkyl which is substituted in the alkyl ether or thioether moiety by C₁ -C₆ -alkoxycarbonyl, R⁴ is hydrogen or C₁ -C₃ -alkyl, Z is methyleneoxymethylene, methylenethiomethylene or ethenylene (--CH═CH--) and R⁵ and R⁶ are each hydrogen or C₁ -C₃ -alkyl, have an advantageous herbicidal action, particularly in the postemergence method, and are selective with respect to a number of crops.

Halogen as used above is fluorine, chlorine or bromine, and halogen radicals R¹ are preferably fluorine and halogen radicals R² are preferably chlorine.

Alkyl (alone or as part of a substituent) includes branched or straight-chain radicals, e.g. methyl or ethyl, n-propyl and isopropyl.

Alkenyl and alkynyl may likewise be branched or straight-chain. Examples of alkenyl radicals in the formula I are allyl, 2-butenyl, 3-butenyl, 2-isobutenyl, 2-pentenyl, 3-pentenyl and 4-pentenyl, in particular allyl or 2-butenyl, alkynyl is, as a rule, propargyl, 2-butynyl, 3-butynyl or isomeric pentynyl radicals; however, alkynyl is preferably propargyl or 2- or 3-butynyl.

As a substituent of the general formula I, alkoxy is methoxy, ethoxy, n-propoxy, isopropoxy and the four isomeric butoxy radicals, in particular methoxy, ethoxy or isopropoxy. Examples of alkylthio in the formula I are n-propylthio, isopropylthio and n-butylthio, and in particular methylthio and ethylthio.

In the case of substitution in the thioacetal moiety, the formula I embraces enantiomers, diastereomers and their mixtures.

The compounds of the formula I can be considered as N-substituted tetrahydrophthalimides; accordingly, they are obtainable from 3,4,5,6-tetrahydrophthalic anhydride and an aniline of the formula V, for example in a solvent, at from 0° to 150° C., preferably from 20° to 100° C. Examples of suitable solvents are lower alkanoic acids, such as glacial acetic acid and propionic acid, and aprotic solvents, such as toluene and xylene, in the presence of acidic catalysts, such as aromatic sulfonic acids.

Preferred compounds I are those in which R¹ is hydrogen or fluorine, R² is chlorine and A is dithiane, dithiolane, oxathiolane or their substituted analogs.

The anilines of the formula V can be obtained, for example, by reducing an appropriately substituted nitrobenzene IV with a reducing agent, such as iron or a tin(II) salt. ##STR6##

The reduction can also be carried out in the form of catalytic hydrogenation over a metal catalyst, such as platinum, palladium or Raney nickel, under relatively mild conditions.

The nitrobenzenes IV are obtainable by reacting a benzaldehyde II in a solvent with a dithiol or mercaptoalkanol of the formula IIIa or IIIb in the presence of an acid. ##STR7##

The recommended procedures given in the Examples below were used with appropriate modification of the starting compounds to obtain further compounds of the general formula I. The compounds are listed together with physical data in the Tables below. Compounds without such data can be obtained from corresponding substances in a similar manner. Because of their close structural relationship with the compounds prepared and investigated, they are expected to have a similar action.

EXAMPLE ##STR8## a) 9.9 g of ethane-1,2-dithiol are added to 18.6 g of 2-chloro-5-nitrobenzaldehyde and 0.5 g of p-toluenesulfonic acid in 250 ml of toluene, and the mixture is refluxed for 5 hours under a water separator. After the mixture has cooled, the solvent is removed, the residue is stirred with petroleum ether and the product is filtered off and dried. 25.5 g of 4-chloro-3-(1,3-dithiolan-2-yl)-nitrobenzene (mp. 130°-131° C.) are obtained.

b) 24.9 g of the above nitro compound are added a little at a time to a mixture of 15.9 g of iron powder in 50 ml of methanol and 75 ml of glacial acetic acid under reflux, and refluxing is continued for 2 hours. After the mixture has cooled, 250 ml of water are added and the solid is filtered off. The filtrate is extracted with 3 times 100 ml of ethyl acetate, the extracts are dried and evaporated down and the product is precipitated from petroleum ether, filtered off under suction and dried. 21.5 g of 4-chloro-3-(1,3-dithiolan-2-yl)-aniline (mp. 60°-63° C.) are obtained.

c) 11.6 g of the above aniline and 7.6 g of cyclohexene-1,2-dicarboxylic anhydride in 150 ml of glacial acetic acid are stirred for 2 days at room temperature, and the precipitate which separates out is filtered off, washed with water and petroleum ether and dried. 13 g of N-[4-chlorophenyl-3-(1,3-dithiolan-2-yl)]-3,4,5,6-tetrahydrophthalimide (mp. 155°-158° C.) (Table 1 No. 1.001) are obtained.

Other examples of active ingredients which can be synthesized using this principle are shown in Tables 1 to 5.

                  TABLE 1                                                          ______________________________________                                          ##STR9##                                                                      No.  R.sup.1                                                                              R.sup.3          R.sup.4                                                                              n   X   mp. [°C.]                     ______________________________________                                         1.001                                                                               H     H                H     0   S   155-158                              1.002                                                                               F     H                H     0   S   160-161                              1.003                                                                               H     4-CH.sub.3       H     0   S   101-102                              1.004                                                                               F     4-CH.sub.3       H     0   S   138-139                              1.005                                                                               H     4-CH.sub.2 CH.sub.3                                                                             H     0   S                                        1.006                                                                               F     4-CH.sub.2 CH.sub.3                                                                             H     0   S                                        1.007                                                                               H     4-(CH.sub.2).sub.2 CH.sub.3                                                                     H     0   S                                        1.008                                                                               F     4-(CH.sub.2).sub.2 CH.sub.3                                                                     H     0   S                                        1.009                                                                               H     4-CH(CH.sub.3).sub.2                                                                            H     0   S                                        1.010                                                                               F     4-CH(CH.sub.3).sub.2                                                                            H     0   S                                        1.011                                                                               H     4-CH.sub.2 Cl    H     0   S   109-110                              1.012                                                                               F     4-CH.sub.2 Cl    H     0   S                                        1.013                                                                               H     4-CH.sub.2 Br    H     0   S                                        1.014                                                                               F     4-CH.sub.2 Br    H     0   S                                        1.015                                                                               H     4-CH.sub.2 CN    H     0   S   82-84                                1.016                                                                               F     4-CH.sub.2 CN    H     0   S                                        1.017                                                                               H     4-CH.sub.2 OH    H     0   S   88-90                                1.018                                                                               F     4-CH.sub.2 OH    H     0   S                                        1.019                                                                               H     4-CH.sub.2 SH    H     0   S   96-97                                1.020                                                                               F     4-CH.sub.2 SH    H     0   S                                        1.021                                                                               H     4-CH.sub.2 COOCH.sub.3                                                                          H     0   S                                        1.022                                                                               F     4-CH.sub.2 COOCH.sub.3                                                                          H     0   S                                        1.023                                                                               H     4-CH.sub.2 CO.sub.2 CH.sub.2 CH.sub.3                                                           H     0   S                                        1.024                                                                               F     4-CH.sub.2 CO.sub.2 CH.sub.2 CH.sub.3                                                           H     0   S                                        1.025                                                                               H     4-CH.sub.2 OCH.sub.3                                                                            H     0   S                                        1.026                                                                               F     4-CH.sub.2 OCH.sub.3                                                                            H     0   S                                        1.027                                                                               H     4-CH.sub.2 OCH.sub.2 CH.sub.3                                                                   H     0   S                                        1.028                                                                               F     4-CH.sub.2 OCH.sub.2 CH.sub.3                                                                   H     0   S                                        1.029                                                                               H     4-CH.sub.2 SCH.sub.3                                                                            H     0   S   oil                                  1.030                                                                               F     4-CH.sub.2 SCH.sub.3                                                                            H     0   S                                        1.031                                                                               H     4-CH.sub.2 CH.sub.2 SCH.sub.3                                                                   H     0   S                                        1.032                                                                               F     4-CH.sub.2 CH.sub.2 SCH.sub.3                                                                   H     0   S                                        1.033                                                                               H     4-CH.sub.2 OCH.sub.2 CHCH.sub.2                                                                 H     0   S                                        1.034                                                                               F     4-CH.sub.2 OCH.sub.2 CHCH.sub.2                                                                 H     0   S                                        1.035                                                                               H     4-CH.sub.2 OCH.sub.2 CCH                                                                        H     0   S                                        1.036                                                                               F     4-CH.sub.2 OCH.sub.2 CCH                                                                        H     0   S                                        1.037                                                                               H     4-CH.sub.2 OCOCH.sub.3                                                                          H     0   S   80-81                                1.038                                                                               F     4-CH.sub.2 OCOCH.sub.3                                                                          H     0   S                                        1.039                                                                               H     4-CH.sub.2 OCOCH.sub.2 CH.sub.3                                                                 H     0   S                                        1.040                                                                               F     4-CH.sub.2 OCOCH.sub.2 CH.sub.3                                                                 H     0   S                                        1.041                                                                               H     4-CO.sub.2 CH.sub.3                                                                             H     0   S                                        1.042                                                                               F     4-CO.sub.2 CH.sub.3                                                                             H     0   S                                        1.043                                                                               H     4-CO.sub.2 CH.sub.2 CH.sub.3                                                                    H     0   S                                        1.044                                                                               F     4-CO.sub.2 CH.sub.2 CH.sub.3                                                                    H     0   S                                        1.045                                                                               H     4-COOH           H     0   S                                        1.046                                                                               F     4-COOH           H     0   S                                        1.047                                                                               H     4-CH.sub.2 SCH.sub.2 CO.sub.2 CH.sub.3                                                          H     0   S   oil                                  1.048                                                                               F     4-CH.sub.2 SCH.sub.2 CO.sub.2 CH.sub.3                                                          H     0   S                                        1.049                                                                               H     4-CH.sub. 2 SCH.sub.2 CO.sub.2 CH.sub.2 CH.sub.3                                                H     0   S                                        1.050                                                                               F     4-CH.sub.2 SCH.sub.2 CO.sub.2 CH.sub.2 CH.sub.3                                                 H     0   S                                        1.051                                                                               H     4-CH.sub.2 OCH.sub.2 CO.sub.2 CH.sub.3                                                          H     0   S                                        1.052                                                                               F     4-CH.sub.2 OCH.sub.2 CO.sub.2 CH.sub.3                                                          H     0   S                                        1.053                                                                               H     4-CH.sub.2 OCH.sub.2 CO.sub.2 CH.sub.2 CH.sub.3                                                 H     0   S                                        1.054                                                                               F     4-CH.sub.2 OCH.sub.2 CO.sub.2 CH.sub.2 CH.sub.3                                                 H     0   S                                        1.055                                                                               H     4-CH.sub.3       5-CH.sub.3                                                                           0   S                                        1.056                                                                               F     4-CH.sub.3       5-CH.sub.3                                                                           0   S                                        1.057                                                                               H     4-CH.sub.2 SCH.sub.2 CHCH.sub.2                                                                 H     0   S   oil                                  1.058                                                                               F     4-CH.sub.2 SCH.sub.2 CHCH.sub.2                                                                 H     0   S                                        1.059                                                                               H     4-CH.sub.2 SCH.sub.2 CCH                                                                        H     0   S   oil                                  1.060                                                                               F     4-CH.sub.2 SCH.sub.2 CCH                                                                        H     0   S                                        1.061                                                                               H     4-CH.sub.2 SCH(CH.sub.3)CO.sub.2 CH.sub.3                                                       H     0   S   oil                                  1.062                                                                               F     4-CH.sub.2 SCH(CH.sub.3)CO.sub.2 CH.sub.3                                                       H     0   S                                        ______________________________________                                    

                                      TABLE 2                                      __________________________________________________________________________      ##STR10##                                                                     No. R.sup.1                                                                           R.sup.3      R.sup.4 n X  mp. [°C.]                              __________________________________________________________________________     2.001                                                                              H  H            H       0 O  141-142                                       2.002                                                                              F  H            H       0 O                                                2.003                                                                              H  4-CH.sub.3   H       0 O  oil                                           2.004                                                                              F  4-CH.sub.3   H       0 O  oil                                           2.005                                                                              H  4-CH.sub.2 CH.sub.3                                                                         H       0 O                                                2.006                                                                              F  4-CH.sub.2 CH.sub.3                                                                         H       0 O                                                2.007                                                                              H  4-(CH.sub.2).sub.2 CH.sub.3                                                                 H       0 O                                                2.008                                                                              F  4-(CH.sub.2).sub.2 CH.sub.3                                                                 H       0 O                                                2.009                                                                              H  4-CH(CH.sub.3).sub.2                                                                        H       0 O                                                2.010                                                                              F  4-CH(CH.sub.3).sub.2                                                                        H       0 O                                                2.011                                                                              H  4-CH.sub.2 Cl                                                                               H       0 O                                                2.012                                                                              F  4-CH.sub.2 Cl                                                                               H       0 O                                                2.013                                                                              H  4-CH.sub.2 Br                                                                               H       0 O                                                2.014                                                                              F  4-CH.sub.2 Br                                                                               H       0 O                                                2.015                                                                              H  4-CH.sub.2 CN                                                                               H       0 O                                                2.016                                                                              F  4-CH.sub.2 CN                                                                               H       0 O                                                2.017                                                                              H  4-CH.sub.2 OH                                                                               H       0 O  91-93                                         2.018                                                                              F  4-CH.sub.2 OH                                                                               H       0 O                                                2.019                                                                              H  4-CH.sub.2 SH                                                                               H       0 O                                                2.020                                                                              F  4-CH.sub.2 SH                                                                               H       0 O                                                2.021                                                                              H  4-CH.sub.2 CO.sub.2 CH.sub.3                                                                H       0 O                                                2.022                                                                              F  4-CH.sub.2 CO.sub.2 CH.sub.3                                                                H       0 O                                                2.023                                                                              H  4-CH.sub.2 CO.sub.2 CH.sub.2 CH.sub.3                                                       H       0 O                                                2.024                                                                              F  4-CH.sub.2 CO.sub.2 CH.sub.2 CH.sub.3                                                       H       0 O                                                2.025                                                                              H  4-CH.sub.2 OCH.sub.3                                                                        H       0 O                                                2.026                                                                              F  4-CH.sub.2 OCH.sub.3                                                                        H       0 O                                                2.027                                                                              H  4-CH.sub.2 OCH.sub.2 CH.sub.3                                                               H       0 O                                                2.028                                                                              F  4-CH.sub.2 OCH.sub.2 CH.sub.3                                                               H       0 O                                                2.029                                                                              H  4-CH.sub.2 SCH.sub.3                                                                        H       0 O                                                2.030                                                                              F  4-CH.sub.2 SCH.sub.3                                                                        H       0 O                                                2.031                                                                              H  4-CH.sub.2 CH.sub.2 SCH.sub.3                                                               H       0 O                                                2.032                                                                              F  4-CH.sub.2 CH.sub.2 SCH.sub.3                                                               H       0 O                                                2.033                                                                              H  4-CH.sub.2 OCH.sub.2 CHCH.sub.2                                                             H       0 O                                                2.034                                                                              F  4-CH.sub.2 OCH.sub.2 CHCH.sub.2                                                             H       0 O                                                2.035                                                                              H  4-CH.sub.2 OCH.sub.2 CCH                                                                    H       0 O                                                2.036                                                                              F  4-CH.sub.2 OCH.sub.2 CCH                                                                    H       0 O                                                2.037                                                                              H  4-CH.sub.2 OCOCH.sub.3                                                                      H       0 O                                                2.038                                                                              F  4-CH.sub.2 OCOCH.sub.3                                                                      H       0 O                                                2.039                                                                              H  4-CH.sub.2 OCOCH.sub.2 CH.sub.3                                                             H       0 O                                                2.040                                                                              F  4-CH.sub.2 OCOCH.sub.2 CH.sub.3                                                             H       0 O                                                2.041                                                                              H  4-CO.sub.2 CH.sub.3                                                                         H       0 O                                                2.042                                                                              F  4-CO.sub.2 CH.sub.3                                                                         H       0 O                                                2.043                                                                              H  4-CO.sub.2 CH.sub.2 CH.sub.3                                                                H       0 O                                                2.044                                                                              F  4-CO.sub.2 CH.sub.2 CH.sub.3                                                                H       0 O                                                2.045                                                                              H  4-COOH       H       0 O                                                2.046                                                                              F  4-COOH       H       0 O                                                2.047                                                                              H  4-CH.sub.2 SCH.sub.2 CO.sub.2 CH.sub.3                                                      H       0 O                                                2.048                                                                              F  4-CH.sub.2 SCH.sub.2 CO.sub.2 CH.sub.3                                                      H       0 O                                                2.049                                                                              H  4-CH.sub.2 SCH.sub.2 CO.sub.2 CH.sub.2 CH.sub.3                                             H       0 O                                                2.050                                                                              F  4-CH.sub.2 SCH.sub.2 CO.sub.2 CH.sub.2 CH.sub.3                                             H       0 O                                                2.051                                                                              H  4-CH.sub.2 OCH.sub.2 CO.sub.2 CH.sub.3                                                      H       0 O                                                2.052                                                                              F  4-CH.sub.2 OCH.sub.2 CO.sub.2 CH.sub.3                                                      H       0 O                                                2.053                                                                              H  4-CH.sub.2 OCH.sub.2 CO.sub.2 CH.sub.2 CH.sub.3                                             H       0 O                                                2.054                                                                              F  4-CH.sub.2 OCH.sub.2 CO.sub.2 CH.sub.2 CH.sub.3                                             H       0 O                                                2.055                                                                              H  4-CH.sub.3   5-CH.sub.3                                                                             0 O                                                2.056                                                                              F  4-CH.sub.3   5-CH.sub.3                                                                             0 O                                                2.057                                                                              H  H            5-CH.sub.3                                                                             0 O                                                2.058                                                                              F  H            5-CH.sub.3                                                                             0 O                                                2.059                                                                              H  H            5-CH.sub.2 CH.sub.3                                                                    0 O                                                2.060                                                                              F  H            5-CH.sub.2 CH.sub.3                                                                    0 O                                                2.061                                                                              H  H            5-(CH.sub.2).sub.2 CH.sub.3                                                            0 O                                                2.062                                                                              F  H            5-(CH.sub.2).sub.2 CH.sub.3                                                            0 O                                                2.063                                                                              H  H            5-CH(CH.sub.3).sub.2                                                                   0 O                                                2.064                                                                              F  H            5-CH(CH.sub.3).sub.2                                                                   0 O                                                2.065                                                                              H  5-CH.sub.2 Cl                                                                               H       0 O                                                2.066                                                                              F  5-CH.sub.2 Cl                                                                               H       0 O                                                2.067                                                                              H  5-CH.sub.2 Br                                                                               H       0 O                                                2.068                                                                              F  5-CH.sub.2 Br                                                                               H       0 O                                                2.069                                                                              H  5-CH.sub.2 CN                                                                               H       0 O                                                2.070                                                                              F  5-CH.sub.2 CN                                                                               H       0 O                                                2.071                                                                              H  5-CH.sub.2 OH                                                                               H       0 O                                                2.072                                                                              F  5-CH.sub.2 OH                                                                               H       0 O                                                2.073                                                                              H  5-CH.sub.2 SH                                                                               H       0 O                                                2.074                                                                              F  5-CH.sub.2 SH                                                                               H       0 O                                                2.075                                                                              H  5-CH.sub.2 CO.sub.2 CH.sub.3                                                                H       0 O                                                2.076                                                                              F  5-CH.sub.2 CO.sub.2 CH.sub.3                                                                H       0 O                                                2.077                                                                              H  5-CH.sub.2 CO.sub.2 CH.sub.2 CH.sub.3                                                       H       0 O                                                2.078                                                                              F  5-CH.sub.2 CO.sub.2 CH.sub.2 CH.sub.3                                                       H       0 O                                                2.079                                                                              H  5-CH.sub.2 OCH.sub.3                                                                        H       0 O                                                2.080                                                                              F  5-CH.sub.2 OCH.sub.3                                                                        H       0 O                                                2.081                                                                              H  5-CH.sub.2 OCH.sub.2 CH.sub.3                                                               H       0 O                                                2.282                                                                              F  5-CH.sub.2 OCH.sub.2 CH.sub.3                                                               H       0 O                                                2.083                                                                              H  5-CH.sub.2 SCH.sub.3                                                                        H       0 O                                                2.084                                                                              F  5-CH.sub.2 SCH.sub.3                                                                        H       0 O                                                2.085                                                                              H  5-CH.sub.2 OCH.sub.2 CHCH.sub.2                                                             H       0 O                                                2.086                                                                              F  5-CH.sub.2 OCH.sub.2 CHCH.sub.2                                                             H       0 O                                                2.087                                                                              H  5-CH.sub.2 OCH.sub.2 CCH                                                                    H       0 O                                                2.088                                                                              F  5-CH.sub.2 OCH.sub.2 C CH                                                                   H       0 O                                                2.089                                                                              H  5-CH.sub.2 OCOCH.sub.3                                                                      H       0 O                                                2.090                                                                              F  5-CH.sub.2 OCOCH.sub.3                                                                      H       0 O                                                2.091                                                                              H  5-CH.sub.2 OCOCH.sub.2 CH.sub.3                                                             H       0 O                                                2.092                                                                              F  5-CH.sub.2 OCOCH.sub.2 CH.sub.3                                                             H       0 O                                                2.093                                                                              H  5-CO.sub.2 CH.sub.3                                                                         H       0 O                                                2.094                                                                              F  5-CO.sub.2 CH.sub.3                                                                         H       0 O                                                2.095                                                                              H  5-CO.sub.2 CH.sub.2 CH.sub.3                                                                H       0 O                                                2.096                                                                              F  5-CO.sub.2 CH.sub.2 CH.sub.3                                                                H       0 O                                                2.097                                                                              H  5-COOH       H       0 O                                                2.098                                                                              F  5-COOH       H       0 O                                                2.099                                                                              H  5-CH.sub.2 SCH.sub.2 CO.sub.2 CH.sub.3                                                      H       0 O                                                2.100                                                                              F  5-CH.sub.2 SCH.sub.2 CO.sub.2 CH.sub.3                                                      H       0 O                                                2.101                                                                              H  5-CH.sub.2 SCH.sub.2 CO.sub.2 CH.sub.2 CH.sub.3                                             H       0 O                                                2.102                                                                              F  5-CH.sub.2 SCH.sub.2 CO.sub.2 CH.sub.2 CH.sub.3                                             H       0 O                                                2.103                                                                              H  5-CH.sub.2 OCH.sub.2 CO.sub.2 CH.sub.3                                                      H       0 O                                                2.104                                                                              F  5-CH.sub.2 OCH.sub.2 CO.sub.2 CH.sub.3                                                      H       0 O                                                2.105                                                                              H  5-CH.sub.2 OCH.sub.2 CO.sub.2 CH.sub.3                                                      H       0 O                                                2.106                                                                              F  5-CH.sub.2 OCH.sub. 2 CO.sub.2 CH.sub.3                                                     H       0 O                                                __________________________________________________________________________

                  TABLE 3                                                          ______________________________________                                          ##STR11##                                                                     No.  R.sup.1                                                                              R.sup.3          R.sup.4                                                                              n   X   mp. [°C.]                     ______________________________________                                         3.001                                                                               H     H                H     1   S   198-200                              3.002                                                                               F     H                H     1   S                                        3.003                                                                               H     4-CH.sub.3       H     1   S   158-159                              3.004                                                                               F     4-CH.sub.3       H     1   S                                        3.005                                                                               H     4-CH.sub.2 CH.sub.3                                                                             H     1   S                                        3.006                                                                               F     4-CH.sub.2 CH.sub.3                                                                             H     1   S                                        3.007                                                                               H     4-(CH.sub.2).sub.2 CH.sub.3                                                                     H     1   S                                        3.008                                                                               F     4-(CH.sub.2).sub.2 CH.sub.3                                                                     H     1   S                                        3.009                                                                               H     4-CH(CH.sub.3).sub.2                                                                            H     1   S                                        3.010                                                                               F     4-CH(CH.sub.3).sub.2                                                                            H     1   S                                        3.011                                                                               H     4-CH.sub.2 Cl    H     1   S                                        3.012                                                                               F     4-CH.sub.2 Cl    H     1   S                                        3.013                                                                               H     4-CH.sub.2 Br    H     1   S                                        3.014                                                                               F     4-CH.sub.2 Br    H     1   S                                        3.015                                                                               H     4-CH.sub.2 CN    H     1   S                                        3.016                                                                               F     4-CH.sub.2 CN    H     1   S                                        3.017                                                                               H     4-CH.sub.2 OH    H     1   S                                        3.018                                                                               F     4-CH.sub.2 OH    H     1   S                                        3.019                                                                               H     4-CH.sub.2 SH    H     1   S                                        3.020                                                                               F     4-CH.sub.2 SH    H     1   S                                        3.021                                                                               H     4-CH.sub.2 CO.sub.2 CH.sub.3                                                                    H     1   S                                        3.022                                                                               F     4-CH.sub.2 CO.sub.2 CH.sub.3                                                                    H     1   S                                        3.023                                                                               H     4-CH.sub.2 CO.sub.2 CH.sub.2 CH.sub.3                                                           H     1   S                                        3.024                                                                               F     4-CH.sub.2 CO.sub.2 CH.sub.2 CH.sub.3                                                           H     1   S                                        3.025                                                                               H     4-CH.sub.2 OCH.sub.3                                                                            H     1   S                                        3.026                                                                               F     4-CH.sub.2 OCH.sub.3                                                                            H     1   S                                        3.027                                                                               H     4-CH.sub.2 OCH.sub.2 CH.sub.3                                                                   H     1   S                                        3.028                                                                               F     4-CH.sub.2 OCH.sub.2 CH.sub.3                                                                   H     1   S                                        3.029                                                                               H     4-CH.sub.2 SCH.sub.3                                                                            H     1   S                                        3.030                                                                               F     4-CH.sub.2 SCH.sub.3                                                                            H     1   S                                        3.031                                                                               H     4-CH.sub.2 CH.sub.2 SCH.sub.3                                                                   H     1   S                                        3.032                                                                               F     4-CH.sub.2 CH.sub.2 SCH.sub.3                                                                   H     1   S                                        3.033                                                                               H     4-CH.sub.2 OCH.sub.2 CHCH.sub.2                                                                 H     1   S                                        3.034                                                                               F     4-CH.sub.2 OCH.sub.2 CHCH.sub.2                                                                 H     1   S                                        3.035                                                                               H     4-CH.sub.2 OCH.sub.2 CCH                                                                        H     1   S                                        3.036                                                                               F     4-CH.sub.2 OCH.sub.2 CCH                                                                        H     1   S                                        3.037                                                                               H     4-CH.sub.2 OCOCH.sub.3                                                                          H     1   S                                        3.038                                                                               F     4-CH.sub.2 OCOCH.sub.3                                                                          H     1   S                                        3.039                                                                               H     4-CH.sub.2 OCOCH.sub.2 CH.sub.3                                                                 H     1   S                                        3.040                                                                               F     4-CH.sub.2 OCOCH.sub.2 CH.sub.3                                                                 H     1   S                                        3.041                                                                               H     4-CO.sub.2 CH.sub.3                                                                             H     1   S                                        3.042                                                                               F     4-CO.sub.2 CH.sub.3                                                                             H     1   S                                        3.043                                                                               H     4-CO.sub.2 CH.sub.2 CH.sub.3                                                                    H     1   S                                        3.044                                                                               F     4-CO.sub.2 CH.sub.2 CH.sub.3                                                                    H     1   S                                        3.045                                                                               H     4-COOH           H     1   S                                        3.046                                                                               F     4-COOH           H     1   S                                        3.047                                                                               H     4-CH.sub.2 SCH.sub.2 CO.sub.2 CH.sub.3                                                          H     1   S                                        3.048                                                                               F     4-CH.sub.2 SCH.sub.2 CO.sub.2 CH.sub.3                                                          H     1   S                                        3.049                                                                               H     4-CH.sub.2 SCH.sub.2 CO.sub.2 CH.sub.2 CH.sub.3                                                 H     1   S                                        3.050                                                                               F     4-CH.sub.2 SCH.sub.2 CO.sub.2 CH.sub.2 CH.sub.3                                                 H     1   S                                        3.051                                                                               H     4-CH.sub.2 OCH.sub.2 CO.sub.2 CH.sub.3                                                          H     1   S                                        3.052                                                                               F     4-CH.sub.2 OCH.sub.2 CO.sub.2 CH.sub.3                                                          H     1   S                                        3.053                                                                               H     4-CH.sub.2 OCH.sub.2 CO.sub.2 CH.sub.2 CH.sub.3                                                 H     1   S                                        3.054                                                                               F     4-CH.sub.2 OCH.sub.2 CO.sub.2 CH.sub.2 CH.sub.3                                                 H     1   S                                        3.055                                                                               H     4-CH.sub.3       6-CH.sub.3                                                                           1   S                                        3.056                                                                               F     4-CH.sub.3       6-CH.sub.3                                                                           1   S                                        3.057                                                                               H     5-CH.sub.3       5-CH.sub.3                                                                           1   S                                        3.058                                                                               F     5-CH.sub.3       5-CH.sub.3                                                                           1   S                                        ______________________________________                                    

                  TABLE 4                                                          ______________________________________                                          ##STR12##                                                                     No.  R.sup.1                                                                              R.sup.5     R.sup.6                                                                               Z         mp. [°C.]                       ______________________________________                                         4.001                                                                               H     H           H      CHCH                                             4.002                                                                               F     H           H      CHCH                                             4.003                                                                               H     4-CH.sub.3  H      CHCH                                             4.004                                                                               F     4-CH.sub.3  H      CHCH                                             4.005                                                                               H     4-CH.sub.2 CH.sub.3                                                                        H      CHCH                                             4.006                                                                               F     4-CH.sub.2 CH.sub.3                                                                        H      CHCH                                             4.007                                                                               H     4-CH.sub.2 CH.sub.2 CH.sub.3                                                               H      CHCH                                             4.008                                                                               F     4-CH.sub.2 CH.sub.2 CH.sub.3                                                               H      CHCH                                             4.009                                                                               H     4-CH(CH.sub.3).sub.2                                                                       H      CHCH                                             4.010                                                                               F     4-CH(CH.sub.3).sub. 2                                                                      H      CHCH                                             4.011                                                                               H     4-CH.sub.3  7-CH.sub.3                                                                            CHCH                                             4.012                                                                               F     4-CH.sub.3  7-CH.sub.3                                                                            CHCH                                             4.013                                                                               H     H           H      CH.sub.2 OCH.sub.2                                                                       134-135                                4.014                                                                               F     H           H      CH.sub.2 OCH.sub.2                               4.015                                                                               H     4-CH.sub.3  H      CH.sub.2 OCH.sub.2                               4.016                                                                               F     4-CH.sub.3  H      CH.sub.2 OCH.sub.2                               4.017                                                                               H     4-CH.sub.2 CH.sub.3                                                                        H      CH.sub.2 OCH.sub.2                               4.018                                                                               F     4-CH.sub.2 CH.sub.3                                                                        H      CH.sub.2 OCH.sub.2                               4.019                                                                               H     4-CH.sub.2 CH.sub.2 CH.sub.3                                                               H      CH.sub.2 OCH.sub.2                               4.020                                                                               F     4-CH.sub.2 CH.sub.2 CH.sub.3                                                               H      CH.sub.2 OCH.sub.2                               4.021                                                                               H     4-CH(CH.sub.3).sub.2                                                                       H      CH.sub.2 OCH.sub.2                               4.022                                                                               F     4-CH(CH.sub.3).sub.2                                                                       H      CH.sub.2 OCH.sub.2                               4.023                                                                               H     4-CH.sub.3  8-CH.sub.3                                                                            CH.sub.2 OCH.sub.2                               4.024                                                                               F     4-CH.sub.3  8-CH.sub.3                                                                            CH.sub.2 OCH.sub.2                               4.025                                                                               H     H           H      CH.sub.2 SCH.sub.2                               4.026                                                                               F     H           H      CH.sub.2 SCH.sub.2                               4.027                                                                               H     4-CH.sub.3  H      CH.sub.2 SCH.sub.2                               4.028                                                                               F     4-CH.sub.3  H      CH.sub.2 SCH.sub.2                               4.029                                                                               H     4-CH.sub.2 CH.sub.3                                                                        H      CH.sub.2 SCH.sub.2                               4.030                                                                               F     4-CH.sub.2 CH.sub.3                                                                        H      CH.sub.2 SCH.sub.2                               4.031                                                                               H     4-CH.sub.2 CH.sub.2 CH.sub.3                                                               H      CH.sub.2 SCH.sub.2                               4.032                                                                               F     4-CH.sub.2 CH.sub.2 CH.sub.3                                                               H      CH.sub.2 SCH.sub.2                               4.033                                                                               H     4-CH(CH.sub.3).sub.2                                                                       H      CH.sub.2 SCH.sub.2                               4.034                                                                               F     4-CH(CH.sub.3).sub.2                                                                       H      CH.sub.2 SCH.sub.2                               4.035                                                                               H     4-CH.sub.3  8-CH.sub.3                                                                            CH.sub.2 SCH.sub.2                               4.036                                                                               F     4-CH.sub.3  8-CH.sub.3                                                                            CH.sub.2 SCH.sub.2                               ______________________________________                                    

                  TABLE 5                                                          ______________________________________                                          ##STR13##                                                                     No.      R.sup.1 R.sup.3  R.sup.4                                                                              X   mp. [°C.]                           ______________________________________                                         5.001    H       H        H     S                                              5.002    F       H        H     S   104-106                                    5.003    H       CH.sub.3 H     S                                              5.004    F       CH.sub.3 H     S   110-112                                    5.005    H       H        H     O                                              5.006    F       H        H     O                                              5.007    H       CH.sub.3 H     O                                              5.008    F       CH.sub.3 H     O   oil                                        ______________________________________                                    

The herbicidal agents, or the active ingredients on which they are based, may be applied pre- or postemergence. If certain crop plants tolerate the active ingredients less well, application techniques may be used in which the herbicidal agents are sprayed from suitable equipment in such a manner that the leaves of sensitive crop plants are if possible not touched, and the agents reach the soil or the unwanted plants growing beneath the crop plants (post-directed, lay-by treatment).

The application rates depend on the objective to be achieved, the time of the year, the plants to be combated and their growth stage, and are from 0.005 to 3.0, preferably 0.01 to 0.5, kg/ha.

The action of the active ingredients of the formula I on the growth of plants is illustrated in greenhouse experiments.

The vessels employed were plastic flowerpots having a volume of 300 cm³ and filled with a sandy loam containing about 3.0% humus. The seeds of the test plants were sown separately, according to species.

For the postemergence treatment, either plants which had been sown in the pots and grown there were selected, or they were cultivated separately as seedlings and transplanted to the pots a few days before being treated.

Depending on growth form, the plants were grown to a height of from 3 to 15 cm before being treated with the active ingredients which were suspended or emulsified in water and sprayed through finely distributing nozzles. The application rates for postemergence treatment were 0.015 and 0.03 kg/ha.

The pots were set up in the greenhouse, species from warmer climates in warmer areas (20° to 36° C.) and species from moderate climates at 10° to 20° C. The experiments were run for from 2 to 4 weeks. During this time the plants were tended and their reactions to the various treatments assessed.

The assessment scale was 0 to 100, 100 denoting nonemergence or complete destruction of at least the visible plant parts, and 0 denoting no damage or normal growth.

The plants used in the greenhouse experiments belonged to the following species:

    ______________________________________                                         CODE    Botanical name    Common name                                          ______________________________________                                         ABUTH   Abutilon theophrasti                                                                             velvet leaf                                          AMARE   Amaranthus spp.   pigweed                                              CHYCO   Chrysanthemum corinarium                                                                         crown daisy                                          DEDTO   Desmodium tortuosum                                                                              Florida beggarweed                                   GALAP   Galium aparine    catchweed bedstraw                                   IPOSS   Ipomoea spp.      morningglory                                         LAMAM   Lamium amplexicaule                                                                              henbit                                               MERAN   Mercurialis annua annual mercury                                       SOLNI   Solanum nigrum    black nightshade                                     STEME   Stellaria media   chickweed                                            TRZAS   Triticum aestivum spring wheat                                         ZEAMX   Zea mays          Indian corn                                          ______________________________________                                    

In view of the numerous application methods possible, the compounds according to the invention, or agents containing them, may be used in a large number of crop plants for removing unwanted plants. The following crops are examples:

    ______________________________________                                         Botanical name          Common name                                            ______________________________________                                         Allium cepa             onions                                                 Ananas comosus          pineapples                                             Arachis hypogaea        peanuts                                                                        (groundnuts)                                           Asparagus officinalis   asparagus                                              Avena sativa            oats                                                   Beta vulgaris spp. altissima                                                                           sugarbeets                                             Beta vulgairs spp. rapa fodder beets                                           Beta vulgaris spp. esculenta                                                                           table beets,                                                                   red beets                                              Brassica napus var. napus                                                                              rapeseed                                               Brassica napus var. napobrassica                                                                       swedes                                                 Brassica napus var. rapa                                                                               turnips                                                Brassica rapa var. silvestris                                                  Camellia sinensis       tea plants                                             Carthamus tinctorius    safflower                                              Carya illinoinensis     pecan trees                                            Citrus limon            lemons                                                 Citrus maxima           grapefruits                                            Citrus reticulata       mandarins                                              Citrus sinensis         orange trees                                           Coffea arabica (Coffea canephora,                                                                      coffee plants                                          Coffea liberica)                                                               Cucumis melo            melons                                                 Cucumis sativus         cucumbers                                              Cynodon dactylon        Bermudagrass                                           Elais guineensis        oil palms                                              Fragaria vesca          strawberries                                           Glycine max             soybeans                                               Gossypium hirsutum (Gossypium arboreum,                                                                cotton                                                 Gossypium herbaceum, Gossypium vitifolium)                                     Helianthus annuus       sunflowers                                             Helianthus tuberosus    Jerusalem                                                                      artichoke                                              Hevea brasiliensis      rubber plants                                          Hordeum vulgare         barley                                                 Humulus lupulus         hops                                                   Ipomoea batatas         sweet potatoes                                         Juglans regia           walnut trees                                           Linum usitatissimum     flax                                                   Lycopersicon lycopersicum                                                                              tomatoes                                               Malus spp.              apple trees                                            Manihot esculenta       cassava                                                Medicago sativa         alfalfa (lucerne)                                      Mentha piperita         peppermint                                             Musa spp.               banana plants                                          Nicotiana tabacum (N. rustica)                                                                         tobacco                                                Olea europaea           olive trees                                            Oryza sativa            rice                                                   Panicum miliaceum       panic grass                                            Phaseolus lunatus       limabeans                                              Phaseolus mungo         mungbeans                                              Phaseolus vulgaris      snapbeans, green                                                               beans, dry beans                                       Pennisetum glaucum      pearl millet                                           Petroselinum crispum spp. tuberosum                                                                    parsley                                                Picea abies             Norway spruce                                          Abies alba              fir trees                                              Pinus spp.              pine trees                                             Pisum sativum           English peas                                           Prunus avium            cherry trees                                           Prunus domestica        plum trees                                             Prunus dulcis           almond trees                                           Prunus persica          peach trees                                            Pyrus communis          pear trees                                             Ribes sylvestre         redcurrants                                            Ribes uva-crispa        gooseberries                                           Ricinus communis        castor-oil plants                                      Saccharum officinarum   sugar cane                                             Secale cereale          rye                                                    Sesamum indicum         sesame                                                 Solanum tuberosum       Irish potatoes                                         Sorghum bicolor (s. vulgare)                                                                           sorghum                                                Sorghum dochna          sorgo                                                  Theobroma cacao         cacao plants                                           Trifolium pratense      red clover                                             Triticum aestivum       wheat                                                  Vaccinium corymbosum    blueberries                                            Vaccinium vitis-idaea   cranberries                                            Vicia faba              tick beans                                             Vigna sinensis (V. unguiculata)                                                                        cow peas                                               Vitis vinifera          grapes                                                 Zea mays                Indian corn,                                                                   sweet corn, maize                                      ______________________________________                                    

To increase the spectrum of action and to achieve synergistic effects, the N-phenyltetrahydrophthalimides of the formula I may be mixed with each other, or mixed and applied together with numerous representatives of other herbicidal or growth-regulating active ingredient groups. Examples of suitable components are diazines, 4H-3,1-benzoxazine derivatives, benzothiadiazinones, 2,6-dinitroanilines, N-phenylcarbamates, thiolcarbamates, halocarboxylic acids, triazines, amides, ureas, diphenyl ethers, triazinones, uracils, benzofuran derivatives, cyclohexane-1,3-dione derivatives, quinolinecarboxylic acids, (hetero)-aryloxyphenoxypropionic acids and salts, esters and amides thereof, etc.

It may also be useful to apply the N-phenyltetrahydrophthalimides of the formula I, either alone or in combination with other herbicides, in admixture with other crop protection agents, e.g., agents for combating pests or phytopathogenic fungi or bacteria. The compounds may also be mixed with solutions of mineral salts used to remedy nutritional or trace element deficiencies. Non-phytotoxic oils and oil concentrates may also be added.

                  TABLE 6                                                          ______________________________________                                         Herbicidal action and tolerance by a crop on postemergence                     application of 0.03 kg/ha of compound no. 1.001 in the greenhouse               ##STR14##               comp. no. 1.001                                       Test plants   Damage (%)                                                       ______________________________________                                         TRZAS          0                                                               AMARE         100                                                              GALAP         100                                                              IPOSS         100                                                              MERAN         100                                                              ______________________________________                                    

                  TABLE 7                                                          ______________________________________                                         Herbicidal action on postemergence application of compound                     no. 1.003 at a rate of 0.03 kg/ha in the greenhouse                             ##STR15##               comp. no. 1.003                                       Test plants   Damage (%)                                                       ______________________________________                                         ABUTH         100                                                              AMARE         100                                                              DEDTO         100                                                              GALAP         100                                                              IPOSS         100                                                              MERAN         100                                                              SOLNI         100                                                              STEME         100                                                              ______________________________________                                    

                                      TABLE 8                                      __________________________________________________________________________     Control of unwanted broadleaved plants and tolerance by a crop on              postemergence application of 0.015 kg/ha in the greenhouse                      ##STR16##                                                                     Comp. no.                                                                            R.sup.1                                                                          R  ZEAMX                                                                               CHYCO                                                                               GALAP                                                                               LAMAM                                                                               SOLNI                                                                               STEME                                      __________________________________________________________________________     1.002 F H  10   100  100  100  100  100                                        1.003 F CH.sub.3                                                                          15   100  100  100  100  100                                        __________________________________________________________________________ 

We claim:
 1. An N-phenyltetrahydrophthalimide of the formula I: ##STR17## wherein R¹ is hydrogen or halogen, R² is halogen, A is a substituent of the formula: ##STR18## wherein X is oxygen or sulfur; n is 0 or 1; R³ is hydrogen or C₁ -C₆ -alkoxycarbonyl or C₁ -C₃ -alkyl which is unsubstituted or substituted by halogen, cyano, hydroxy, mercapto, C₁ -C₆ -alkoxycarbonyl, C₁ -C₄ -alkoxy, C₁ -C₄ -alkylthio, C₃ -C₆ -alkenyloxy, C₃ -C₆ -alkenylthio, C₃ -C₆ -alkynyloxy, C₃ -C₆ -alkynylthio or C₁ -C₄ -acyloxy, or is hydroxy or carboxy or is C₁ -C₄ -alkoxy-C₁ -C₂ -alkyl or C₁ -C₄ -alkylthio-C₁ -C₂ -alkyl which is unsubstituted or substituted in the alkylether or thioether moiety by C₁ -C₆ -alkoxycarbonyl; R⁴ is hydrogen or C₁ -C₃ -alkyl; Z is methyleneoxymethylene, methylenethiomethylene or ethenylene; R⁵ is hydrogen or C₁ -C₃ -alkyl; and R⁶ is hydrogen or C₁ -C₃ -alkyl, independently of the steric configuration, with the proviso that n is 1 when R³ and R⁴ are both hydrogen.
 2. The N-phenyltetrahydrophthalimide of claim 1, wherein R¹ is hydrogen or fluorine, R² is chlorine and A is dithiolane or oxathiolane rings, which are unsubstituted or substituted.
 3. The N-phenyltetrahydronaphthalimide of claim 1, wherein A is ##STR19##
 4. The N-phenyltetrahydronaphthalimide of claim 1, wherein A is ##STR20##
 5. The compound of claim 2 having the formula: ##STR21##
 6. A compound according to claim 2 wherein R¹ is H, R² is chloro, and A is ##STR22##
 7. A compound according to claim 2 wherein R¹ is F, R² is Cl, and A is ##STR23##
 8. A compound according to claim 2 wherein R¹ is H, R² is Cl, and A is ##STR24##
 9. A compound according to claim 2, wherein R¹ is F, R² is F, and A is ##STR25##
 10. A compound according to claim 2 wherein R¹ is F, R² is F, and A is ##STR26##
 11. A compound according to claim 2 having the formula: ##STR27##
 12. A herbicidal agent, comprising an effective amount of one or more compounds of the formula I as set forth in claim 4, and one or more auxiliaries, extenders or diluents.
 13. The herbicidal agent of claim 12, wherein for the compound of the formula I, R¹ is hydrogen or fluorine, R² is chlorine and A is dithiolane or oxothiolane rings, which are unsubstituted or substituted.
 14. A process for combating the growth of unwanted plants, which comprises applying to said plants or their habitat or both a herbicidally effective amount of one or more N-phenyltetrahydrophthalimide compounds of the formula I as set forth in claim
 1. 15. The process of claim 14, wherein for the compound of the formula I, R¹ is hydrogen or fluorine, R² is chlorine and A is dithiolane or oxothiolane rings, which are unsubstituted or substituted.
 16. The process of claim 14, wherein said herbicidally effective amount is from about 0.005-3.0 kg/ha.
 17. The process of claim 16, wherein said herbicidally effective amount is from about 0.01-0.5 kg/ha.
 18. The process of claim 16, wherein said herbicidally effective amount is from about 0.015-0.03 kg/ha for post-emergence treatment. 